The present invention relates to an engine case for a gas turbine engine.
A gas turbine engine, such as a turbofan engine for an aircraft, includes a fan section, a compression section, a combustion section, and a turbine section. An axis of the engine is centrally disposed within the engine, and extends longitudinally through these sections. A primary flow path for working medium gases extends axially through the engine. A secondary flow path for working medium gases extends radially outward of the primary flow path.
The secondary flow path is typically defined by a bypass duct formed from a multiple of portions which are fitted together along a flange arrangement. Although effective for metallic duct structures, composite bypass ducts for military engines require other interface arrangements. The viability of turned-up axial flanges on composite components may be relatively low due to a lack of duct circumferential stiffness at mid-span. Additional difficulties may arise in mitered turned-up axial and circumferential flanges.